Question

I have no idea what equation/equations to use to find the answer...please help!!!! A girl who is learning karate is going to break four bricks with her hand. Her hand and arm mass is 1.56 kg. Each brick has a mass of 4.5 kg and is stacked on top of each other. If her hand hits the bricks with a velocity of 16 m/s and comes to a stop on 0.059 seconds, what is the force delivered to the bricks?